Sand-blast machine.



J. L. DAWESI SAND BLAST MACHINE. APPLICATION FILED JUNE 16. 1915.

Patented Feb. 29, 1916.

2 SHEETSSHEET I.

INVENTOR- J. L. DAWES.

SAND BLAST MACHINE.

APPLICATION FILED JUNE I6. 1915.

1,173,178. 1 Patented Feb. 29,1916.

2 SHEETS-SHEET 2.

INVENTOR.

ATTO R N EVE Jenni... Dawes, orr'rr rsauaen, rann'srnvarrm.

SAND-BLAST: MACHINE.

awaits.

. To all whom it may concern: Be it'known that 1, Jean L. Dawes, residing atPittsburgh, in the'countyof Adlegheny and State of Pennsylvania, a citlzen 'of. the United States, have'mvented or discovered certain-new and useful Improvements in Sand-Blast'Machines, of which 1mprovement the following isa specification. My invention relates to. sand blast machines, and the object thereof is to provide a machine suitable for sand blastmg various shaped articles, but which is particularly adapted to sand blast the substantially plane faces of disk-shaped lamp globes A further object of my mventlon is to provide a machine so constructed that the bearings of operating or movable parts w1llnot be cut or worn by the sand.

In the accompanying sheets of drawings,

which form part of my specification, I have illustrated the preferred embodiment of my invention.

Figure 1 is a side elevation of the machine; Fig. 2 a sectional view taken on the line II-11, Fig. 1; Fig. 3 a detail sectional view taken on the line III-IH,-Fig. 2;- Fig. 4 a further detail sectional View taken on the line I'V IV, Fig. 2'; but showing a plate in sandblasting position rather than the--;-globe of Figs.f-1 and 2'; vFig. 5 a.

* view, similar to. the upper portion of Fig.2, but showing a spherical lamp globe mounte ed on difierent, turning mechanism than that of Fig. 2;;Fig; 6' a sectional view to enlarged'scale' of the blastnozzle; and Fig. 7. a sectionalf view. ,to. enlarged scale of" thesand receiver.

.1 In the" seve Hkeimmemlsi are p Y "used to designa '1' p i v In the zpracticepf my. invention the sand blasting takes place within erasing adapted vto retain the fs'and ian'd dust, and means are.

provided. within the. casing for. supporting andmoving.various forms of articles .to'be '45 sand blasted}; Furthermore,means,operated by-mechanism outside of the casing, are provided 'for reciprocatingfthd blast; nozzle within the'casing' The casing may be, of any suitable shape,

but,fas shown herein,-j is preferably 'rectan gular, comprising side walls '1 and 2, endwalls-'3 and 4, and top 5-. .The lower por r tion of the-casing is provided with a parti tion 6, which, with-the casing walls, forms a sand bin 7. The sand blast nozzle may be a of. any suitable construction, that shown ing treatment ofv such globe faces.

particularly in Fig. 6. comprising a T-fitting to one leg of which'there. is attached a d scharge tip 9, to another lega flexible hose 10, leading to the sand bin 7, and to the third leg a pipe 11, which, through a second IT-fitting 12, is attached to a flexible air supply hose 13. To the end that the flow of sand through the hose 10 will be even and continuous, 'a sand receiver 14, provided with perforations 15,.is attached to the lower end of such hose and embedded in the sand within the bin 7. The sand strained through the perforations 15 will, by the suction of the air escaping from'the p pe 11, be drawn upwardly through the hose 10 and projected.v against an object to be sand blasted.

Mechanism is provided for reciprocating the nozzle, and is constructed and arranged m such a manner that there will be no relatively-movable machine-bearing parts exposed to the floating sand particles within the casing. For this purpose the side wall 1 is provided with a vertically disposed slot 16, through which there extends a-rod 17, attached at its inner end to the T-fitting 12, and at its outer end slidably mounted on a suitable guide 18. The rod 17 is reciprocated vertically by means of a pitman 19, adjustably connected to a crank arm 20, secured to a shaft 21, which shaft may be driven in -any suitable manner," as by a -belt 22.

ports 24 to'which-the' guide 18 is attached.

j While, aswill be presently explained, my machine may be employed for sand blasting various shaped articles; it is. particularly adapted; to sand blastthe substantially plane .faces of disk-shapedlamp' globes, such a 10m globe being shown in Figs. 2 and 3. Here-' .tofore considerable difliculty has been ex- "perienced in efi'ecting an even sand blast- In the mechanism which provide for this pur- '-pose, the plane face of the globe to be sand blasted is held'perpendicular to the lineof-blast, and the globe is rotated upon an axis passing through substantially the center of,'and perpendicular to, such face. 1W

seen in Figs. 2 and 3, a shaft'25 is mounted the sidewall 2, and is adapted to be v Patented-Feb. 29, 11916.. Application filed J'une18,1915. eel-intestate.

rotated by a belt 26 extending from the shaft 21. The inner end of the shaft 25 is provided with a transverse bar 27 to which arms 28 are adjustably connected, such arms being provided with adjustable globe-engaging members 29. a

It will be observed that, by such an arrangement, the vertical movement of the nozzle will be harmonic, or stated difierently, will be more ra id when in line with the center of the -glo e face than when in line with the outer edge thereof, the rate of movement of the. nozzle varying gradually as it moves to and from the center of such face. Thus there will be a substantially even sand blasting treatment of the entire area of the circular globe face.

In the machine shown herein means are also, provided for carrying a plate or like article transversely to the line of sand blast.

For this .purpose I preferably provide a conveyer belt 30, driven by a belt wheel 31, keyed to a shaft 32, which shaft in turn may be driven by a belt 33. The shaft 32 is supported, on .abracket 34 attached to the casing wall 3, and a second bracket 35, attached to the wall 4, supports an idler 36 for the conveyer belt. As will be seen, the walls 3 and 4are provided with doors 37 and 38, respectively, so that plates may be placed upon and removed from the belt 30, as well as forgeneral access to the casing. For supporting the u per ends of plates I provide a pivoted rac 39, which, as shown in Fig. 4, may be swung downwardly to holda plate41 from falling rearwardly, or when not needed, may, as shown in .Figs. 2 and 5, be retained in an upward pbsition by catches 40. It will be understood of this feature of my machine that the conveyer may be moved at the proper speed to ermit a plate carried. thereon to be sand lasted by the reciprocating nozzle.

Means are also provided for holding and rotatin a substantially cylindrical lamp lobe in front of the sand blast nozzle.

his is shown particularly in Fi 5, wherein a lobe 42 is suitably attac ed to the end 0 a shaft 43 rotatably mounted in the casing top 5, and, through bevel pinions 44 and 45, driven by the? ower shaft 21.

To the end that the'f ust andfloating particles of sand may-be removed from the casing,-a suction dust conveyor 46 is attached to the topof thacasing.

I claim as my invention:

1.'In a sand blast machine, the combina tion of a closed casing, a sand blast nozzle within said casing mounted for rectilinear reciprocation, a rotatable member, a pi'tman connected to said nozzle andeccentrically to said member, a blank holder rotatable upon an axis substantially coincident with the axis of said'nozzle when in its intermediate position and, coordinated means for rotating said member and blank holder.

2. In a sand blast machine, the combination of a closed casing, a sand blast nozzle within the casing, mounted for rectilinear reciprocation, a rotatable member, a pitman connected to sald nozzle-and eccentrically to said member, a blank holder comprising a rotatable shaft having its-axis substantially coincident with that ofv the nozzle at its Intermediate position, rods extending transversely of and attached tosaid shaft, arms secured to said'rods and adjustable radially with'relation to saidishaft, and 'ad-. justable blank-engaging members secured In testimony whereof I havehereunto set to such arms. 

